Mr. Gerald Golin, Washington, D.C. (appointed by the District Court) for appellant.

Mr. Anthony G. Amsterdam, Asst. U.S. Atty., with whom Messrs. David C. Acheson, U.S. Atty., Charles T. Duncan, Principal Asst. U.S. Atty., and Harry T. Alexander, Asst. U.S. Atty., at the time the brief was filed, were on the brief, for appellee. Messrs. Nathan J. Paulson and David J. McTague, Asst. U.S. Attys., also entered appearances for appellee.

Appellant relied solely upon the defense of insanity in a jury trial which culminated in his conviction for housebreaking with intent to commit an assault, assault with intent to rape, and assault with a dangerous weapon. He alleges that the District Court erred in (1) determining his competency to stand trial, (2) excluding diagnostic opinions of two defense psychiatrists on the ground that their opinions were without ‘proper basis,’ (3) instructing the jury to disregard the testimony on three defense psychologists that appellant had a mental disease or defect on the ground that ‘a psychologist is not competent to give a medical opinion as to a mental disease or defect,’ and (4) depriving him of a fair trial by conducting a lengthy and disparaging examination of some expert witnesses.